1. Field of the Invention
This invention relates to lubricant compositions and, in one of its aspects, relates more particularly to lubricant compositions having improved properties for prevention of metal corrosion.
Still more particularly, in this aspect, the invention relates to lubricant compositions in the form of lubricating oils and greases containing additives effective for inhibiting metal corrosion.
2. Description of the Prior Art
The prior art has long recognized that lubricants, in the form of lubricating oils and greases, apart from performing their intended functions of lubricating metal parts, also exhibit the characteristic of permitting corrosion of metal surfaces with which they may come into contact. In order to control such corrosion, various additives have been suggested. Some of these additives have not proved to afford any appreciable improvement, while others, although more effective, have been found to be too costly.
One such prior art corrosion inhibitor is described in U.S. Pat. No. 2,836,564 as condensation products of alpha halogenated mono-carboxylic acid with 2,5-dimercapto-1,3,4-thiadiazole. Such materials are relatively insoluble in lubricating oils.